What is the danger of heavy rain?

[Guest Jozef_K]

Now that I have FSFlightMax, rain and thunderstorms are displayed on the radar screen, so I can avoid those areas. But what is (in real life) the danger of rain for an aircraft? I can imagine that thunderstorms can be dangerous, but rain?Could someone make me a bit wiser?Jozef http://www.dse.nl/~joker32/pictures/signature.jpg

[Splash_One 0]

Hey,Some reasons are Visibility- it can drop steeply in heavy rainHeavy rain can turn to hail (at higher altitudes)- which can lead to corrosion and cracks on windows. Hail size ranges from rice grain or pea size, to golf ball, tennis ball, cricket ball, and even softball size. Largest i've encountrered were golf balls(Luckily it was in a car , though!). Obviously extremely dangerous and something you want to avoid. I;m sure there are tons more but their not popping up in my head, sorry . :-)Jay :-wave

[Guest]

Hi JozefTo add a little bit more to this discussion-If you have access to any of the books on air disasters check on two accidents that occured in the US.On 4/4/'77 a Southern Airlines DC-9 Flt 242 tried to weave thru some thunderstorm cells. It suffered a dual flameout and massive hail damage (indicative of convective currents of a thunderstorm). They could not restart the engines and went down on a rural road.In August of 1966 a BAC-111 operated by Braniff was thought to be clear of active cells got ripped apart in flight by a "gust event" in flight.There are cases where a jet flying through heavy downpours will suffer a flame-out due to ingestion though it is a transiant event since the crew positions the ignition system to "Continous" to relight the engines in such an event.Runways are engineered to drain quickly and are groved to keep the wheels from hydroplanning when landing. However the left-over rubber etc will make the last 1500' slippery. Taxi ways and high-speed turn-offs can be tricky as well. If you look at the NTSB (www.NTSB.GOV) website at the monthly summary you will find a lot of weather-related "slides-for-life" on watery runways at smaller airfields.Most biz-jets and all the heavy-iron have anti-skid brakes that came in long before the automotive ABS on cars. Another fun bit of trivia is if you ever ride on a DC-9 look at the wing top by the wing-root. You will see two yellow triangles with a bit of yarn. The DC-9 when it was originally design was to be a short-haul type of plane with a lot of stages flown in a day. As the plane was modified it took on longer flights an stayed at altitude longer "cold-soaking" the wing and the fuel inside the wing.As the plane decended into a rain/high moisture environment the water would freeze as it impacted the wing. From what I have heard the yarn was the only reliable way of detecting clear-ice that may have built-up. That is the story I have heard on that....Tim_757